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      <title>事件驱动模型 - 交互式测验</title>
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    <body>
      <div class="main-wrapper">
          <div class="quiz-container">
            <div class="quiz-header">
              <h1>事件驱动模型 - 交互式测验</h1>
              <p>检验你对文档内容的理解程度</p>
            </div>
            <div id="quiz-content">
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                    <div id="hint-container" class="hint-container"></div>
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      <script>
        const quizData = [
  {
    "question": "根据文档，与传统的阻塞I/O模型相比，Netty采用事件驱动模型最核心的目的是什么？",
    "options": [
      "提高并发性能并减少系统资源开销",
      "简化编程模型，让代码更容易编写",
      "实现跨语言的远程过程调用",
      "增强网络传输的安全性"
    ],
    "correctAnswerIndex": 0,
    "explanation": "文档明确指出，传统阻塞I/O模型会导致大量线程等待，浪费计算资源。Netty采用事件驱动模型的核心目的就是为了解决这个问题，通过事件循环处理I/O操作，避免了线程的频繁轮询和上下文切换，从而显著提高并发性能并减少系统开销。",
    "source": "文档中「为什么 Netty 采用事件驱动模型？」部分",
    "hint": "思考一下传统阻塞I/O模型在高并发场景下的主要缺点是什么，Netty的设计又是如何解决这个问题的。"
  },
  {
    "question": "在Netty的事件驱动模型中，`ChannelPipeline`（通道流水线）扮演了什么关键角色？",
    "options": [
      "它是一个负责创建和管理网络连接的工厂",
      "它是一个处理器链，按顺序组织多个`ChannelHandler`来处理事件",
      "它是用于临时存储待处理事件的缓冲队列",
      "它直接负责底层的网络数据读写操作"
    ],
    "correctAnswerIndex": 1,
    "explanation": "`ChannelPipeline`是一个处理器链（Handler Chain），它包含了多个`ChannelHandler`。当一个事件（如数据读取）发生时，该事件会在`ChannelPipeline`中从一个`ChannelHandler`传递到下一个，依次进行处理。这种设计实现了处理逻辑的解耦、复用和灵活扩展。",
    "source": "文档中「Netty 中的事件驱动模型如何工作？」部分的 ChannelPipeline（通道流水线）",
    "hint": "文档中提到了一个“流水线”的概念，它由多个“处理器”组成，用于对事件进行一步步的加工处理。"
  },
  {
    "question": "关于Netty中`EventLoop`和`Channel`（网络连接）之间的关系，以下哪个描述是正确的？",
    "options": [
      "一个`Channel`在其生命周期内可以被多个`EventLoop`轮流处理以实现负载均衡",
      "一个`EventLoop`在其生命周期内只能处理一个`Channel`，保证专一性",
      "一个`Channel`在其生命周期内只会被分配给一个固定的`EventLoop`进行处理",
      "`EventLoop`只负责监听连接请求，不处理任何`Channel`上的I/O事件"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档中明确指出：'一个EventLoop在其生命周期内通常会处理多个连接，但每个连接只能由一个EventLoop处理。' 这意味着一个连接（Channel）一旦被注册到一个EventLoop，就会由这个EventLoop负责其所有的事件处理，这种设计保证了处理的顺序性，并避免了多线程并发访问同一个Channel所带来的复杂性。",
    "source": "文档中「Netty 中的事件驱动模型如何工作？」部分的 EventLoopGroup（事件循环组）",
    "hint": "文档中强调了一个连接和一个事件循环之间的绑定关系，这种设计是为了避免在处理单个连接时出现多线程并发问题。"
  },
  {
    "question": "根据文档对事件驱动模型基本构成的描述，以下哪一项不属于其核心组成要素？",
    "options": [
      "事件循环 (Event Loop)",
      "事件处理器 (Handler)",
      "线程池 (Thread Pool)",
      "事件 (Event)"
    ],
    "correctAnswerIndex": 2,
    "explanation": "根据文档，事件驱动模型的基本构成是：1. 事件（如数据到来）；2. 事件循环（检测并分发事件的核心）；3. 事件处理器（执行具体逻辑）。虽然Netty内部实现中会使用线程（如NioEventLoopGroup管理的线程），但“线程池”本身并不是事件驱动模型这个抽象概念的三个基本构成要素之一。",
    "source": "文档中「事件驱动模型的基本构成」部分",
    "hint": "回顾文档中对事件驱动模型基本构成的定义，它明确列出了三个核心组成部分。"
  },
  {
    "question": "在Netty中，如果需要处理服务器发送给客户端的响应数据，应该优先考虑使用哪种类型的`ChannelHandler`？",
    "options": [
      "ChannelInboundHandler",
      "ChannelInitializer",
      "ChannelOutboundHandler"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档中对`ChannelHandler`的分类有明确说明：`ChannelOutboundHandler`用于处理出站（Outbound）数据，即从系统内部流向外部的数据，例如服务器发送给客户端的响应。相对地，`ChannelInboundHandler`用于处理入站（Inbound）数据，如客户端发送的请求。",
    "source": "文档中「Netty 中的事件驱动模型如何工作？」部分的 ChannelHandler（通道处理器）",
    "hint": "思考一下数据流动的方向：“入站”（Inbound）和“出站”（Outbound）分别代表什么？"
  },
  {
    "question": "根据文档描述，Netty的事件驱动模型能够高效支持高并发连接的关键在于什么？",
    "options": [
      "通过为每个连接创建一个独立的物理线程来实现完全隔离",
      "通过非阻塞I/O和事件循环机制，用较少的线程处理大量的连接",
      "通过先进的数据压缩算法显著减少网络传输的数据量",
      "通过将所有业务逻辑都编译成原生机器码来提升执行速度"
    ],
    "correctAnswerIndex": 1,
    "explanation": "文档在「事件驱动模型的优势」部分明确指出，Netty通过事件驱动和非阻塞I/O，可以轻松支持数万级的并发连接，而无需大量的线程池资源。其核心在于用一个线程（EventLoop）来处理多个连接上的事件，避免了传统阻塞模型中“一个连接一个线程”所带来的巨大线程创建和上下文切换开销。",
    "source": "文档中「事件驱动模型的优势」部分",
    "hint": "高并发的关键在于如何用更少的系统资源（特别是线程）服务更多的客户端。"
  },
  {
    "question": "在文档提供的Echo服务器案例中，`EchoServerHandler`类的核心作用是什么？",
    "options": [
      "初始化服务器的端口和相关配置",
      "管理`bossGroup`和`workerGroup`两个线程组的生命周期",
      "接收客户端发送的数据，并将其原样写回客户端",
      "负责创建新的`SocketChannel`并将其注册到`EventLoop`"
    ],
    "correctAnswerIndex": 2,
    "explanation": "在代码示例中，`EchoServerHandler`继承了`SimpleChannelInboundHandler`，并重写了`channelRead0`方法。该方法的核心逻辑是 `ctx.writeAndFlush(msg)`，即接收到消息(msg)后，立即通过上下文(ctx)将其写回并刷新到通道中，这精确地实现了“回声”（Echo）的功能。",
    "source": "文档中「实际案例：基于事件驱动模型的实现」部分",
    "hint": "请仔细分析`EchoServerHandler`类中的`channelRead0`方法的具体代码实现。"
  }
];
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            const totalQuestions = quizData.length;
            const answeredCount = userAnswers.filter(a => a !== null).length;
            const wrongCount = answeredCount - correctCount;
            const skippedCount = totalQuestions - answeredCount;
            const accuracy = totalQuestions > 0 ? Math.round((correctCount / totalQuestions) * 100) : 0;
            const errorRate = totalQuestions > 0 ? Math.round((wrongCount / totalQuestions) * 100) : 0;

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                '<h3>得分</h3>' +
                '<p>' + correctCount + ' / ' + totalQuestions + '</p>' +
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                '<div class="score-card">' +
                '<h3>正确率</h3>' +
                '<p>' + accuracy + '%</p>' +
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                '<div class="score-card">' +
                '<h3>错误率</h3>' +
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                '<div class="score-card score-details">' +
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                '<tr><td>错误</td><td>' + wrongCount + '</td></tr>' +
                '<tr><td>未答</td><td>' + skippedCount + '</td></tr>' +
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                '</div>' +
                '</div>' +
                '<div class="report-actions">' +
                '<button id="review-btn">回顾测验</button>' +
                '<button class="primary" onclick="location.reload()">再试一次</button>' +
                '</div>' +
                '</div>';

            let reportEl = document.querySelector('.final-score-container');
            if (reportEl) {
                reportEl.remove();
            }
            quizContentEl.insertAdjacentHTML('beforeend', finalScoreHtml);
            document.getElementById('review-btn').addEventListener('click', reviewQuiz);
        }

        function reviewQuiz() {
            const reportEl = document.querySelector('.final-score-container');
            if (reportEl) {
                reportEl.remove();
            }

            document.querySelector('.quiz-body').style.display = 'block';
            document.getElementById('quiz-footer').style.display = 'flex';
            
            currentQuestionIndex = 0;
            loadQuestion();
            updateNavigationButtons(); // Ensure nav buttons are correctly displayed
        }

        // Event Delegation for options
        optionsListEl.addEventListener('click', (event) => {
            if (event.target && event.target.matches('li.option-item')) {
                // Check if the question has already been answered
                if (userAnswers[currentQuestionIndex] === null) {
                    const selectedIndex = parseInt(event.target.dataset.index, 10);
                    selectOption(selectedIndex);
                }
            }
        });

        prevBtn.addEventListener('click', goToPreviousQuestion);
        nextBtn.addEventListener('click', goToNextQuestion);
        hintBtn.addEventListener('click', showHint);
        
        // 初始加载
        loadQuestion();
      </script>
    </body>
    </html>
  